Laser rangefinders include a transmitter channel for transmitting a collimated light beam toward a target, a receiver channel for receiving and processing light reflected from the target, and an optical sighting channel through which the user could sight on the target. Coaxiality of the channels provides a number of benefits, including boresight stability over temperature and vibration, and reduction of weight and size of the rangefinder resulting from sharing of the optical paths. Conventional rangefinders have required complex beamsplitters to have the sighting, transmitting and receiver channels coaxial.